Non-volatile memory is computer memory that can get back stored information even when not powered. Types of non-volatile memory may include resistive RAM (random access memory) (RRAM or ReRAM), phase change RAM (PCRAM), conductive bridge RAM (CBRAM), ferroelectric RAM (F-RAM), etc.
Resistance memory elements, such as resistive RAM, or ReRAM, can be programmed to different resistance states by applying programming energy. After programming, the state of the resistive memory elements can be read and remains stable over a specified time period. Large arrays of resistive memory elements can be used to create a variety of resistive memory devices, including non-volatile solid state memory, programmable logic, signal processing, control systems, pattern recognition devices, and other applications. Examples of resistive memory devices include valence change memory and electrochemical metallization memory, both of which involve ionic motion during electrical switching and belong to the category of memristors.
Memristors are devices that can be programmed to different resistive states by applying a programming energy, for example, a voltage or current pulse. This energy generates a combination of electric field and thermal effects that can modulate the conductivity of both non-volatile switch and non-linear select functions in a memristive element. After programming, the state of the memristor can be read and remains stable over a specified time period.